Property of electron emission under irradiation of ultraviolet ray and applying field

A microchannel plate was used to measure emitted electrons under high field and ultraviolet irradiation of a cathode within the range of 10/sup -19/ A to 10/sup -15/ A in high vacuum (1.3*10/sup -5/ Pa). It is found that photoelectrons are mainly emitted from a flat part of the cathode surface. The number of the electrons is kept constant below the inception field strength of the field emission. The inception field strength of the field emission does not depend on photon energy. The effect of the photon energy on the electron emission from the minute projections did not appear.<
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